8 o8 
Journal of Agricultural Research 
Vol. V, No. 17 
of about 150 penetration has been noted by the authors in this connec¬ 
tion. The theory has been advanced that the ice-water cooling produces 
a set in the material which is not attained by the sample if it is allowed 
to air-cool until it has stood for a number of days. It has been further 
argued that the penetration at this set represents more accurately the 
true consistency of the material than does the penetration determined 
by the method first described. In order to study this matter thoroughly, 
different samples of each of the 12 materials were cooled and prepared 
for testing in a variety of ways, careful attention being paid to the time 
during which the sample was*subjected to a given condition. These con¬ 
ditions are shown in Table II. 
For each test under a given set of conditions samples of materials were 
melted and poured at the same time. In methods 1 to 6 and 15 to 23, 
inclusive, the melted samples were poured into the test dishes and, after 
standing in air for the periods indicated, were immersed in a water bath 
carefully maintained at 25 0 C. for the time selected, prior to determining 
their penetration. At the expiration of this time they were tested in the 
water bath. In methods 7 to 10, inclusive, the melted samples were poured 
into test dishes which had been previously packed in ice. Here they were 
allowed to remain until transferred to the 25 0 water bath. In methods 
11 to 14, inclusive, the melted samples were first poured into the test dishes 
and allowed to cool in air as indicated, after which they were placed in 
an ice-water bath for definite periods of time and then immediately trans¬ 
ferred to the 25 0 water bath. In methods 24 and 25, the melted samples 
were poured into test dishes packed in crushed ice and kept there for 1 
hour. They were then removed and allowed to remain in air for 28 days, 
after which they were placed in the 25 0 water bath just prior to testing 
as indicated. 
